The present invention relates to small lightweight portable hand held foam generation equipment, a foamable liquid non-repellant pesticide formulation that includes a non-repellant, nonionic adjuvant (foaming agent), and to a method of controlling pests with the foamable liquid non-repellant pesticide formulation. The foam generation equipment of the present invention is particularly well suited for introducing foamed pesticides into walls and other confined or enclosed building locations infested with pests and for dispensing foamed pesticides over the entrances of and into the passageways used by pests as well as into pest habitats. The light weight portable hand held foam generation equipment of the present invention also may be used for numerous other pest control applications, such as but not limited to, the application of herbicides and pesticides in the turf industry; the application of enzymes to drains in the sanitation industry; and the application of fungicides and pesticides in the tree and shrub industry. In addition to the various forms of pest control mentioned above, the light weight portable hand held foam generation equipment of the present invention may be used for many other applications where complete coverage of the surfaces, especially, though not limited to, the enclosed or relatively inaccessible surfaces of an enclosed space, cavity, or tubular structure with a coating and/or impregnating material is desired.
Conventional methods for controlling pest infestations, such as but not limited to termite infestations, include: the injection of pesticides beneath the slab and into the soil adjacent the perimeter of infested structures to create pesticide barriers; the location of pesticide containing bait stations in the soil adjacent the perimeter of infested structures, the fumigation of infested structures with pesticides; and the introduction of foamed pesticides into the walls and other enclosed spaces of infested structures such as disclosed in U.S. Pat. No. 6,290,992, issued Sep. 19, 2001. These methods for controlling pest infestations have been in use since at least the mid to late 1980xe2x80x2s and, in the past, have utilized pest repellant pesticides.
In recent years non-repellant pesticides have been introduced into the pest control industry and utilized to control pests, such as termites, by the various methods discussed above. For these types of non-repellant pesticides to be most effective, the pests must move freely about the treated space, area or habitat and not recognize any repellant conditions. It is not necessary for the pests to feed directly on the pesticides or baits containing the pesticides. These non-repellant pesticides are lethal or injurious to pests through contact as well as through ingestion and/or transferal. When a pest comes in contact with the pesticide at least a few molecules of the pesticide adhere to the pest. These few molecules initiate a chemical and/or biological action within the pest that is injurious or lethal to the pest without any ingestion of the pesticide. In addition, pests contaminated with the pesticide then carry the pesticide back to the colony habitat or nest. Since many pests, such as termites, are social, other pests will groom the contaminated pests, and in turn, be groomed by other pests to spread the pesticide contamination throughout the colony. In addition, typically, pests killed by the pesticide will be eaten by other pests in the colony to further spread the pesticide throughout the colony. In this way, the entire colony, including the reproductive(s) of the colony, are destroyed.
Since the repeated and continued passage of a number pests through the treated spaces or areas for a period of time is desired so that numerous pests quickly convey the non-repellant pesticide back to and/or through a colony nest or habitat to spread the pesticide throughout the colony, for this type of non-repellant pesticide to work most effectively when applied in the form of a foam, not only the pesticide but the foamable liquid pesticide formulation made from the pesticide should be non-repellant. In other words, any adjuvant added to the non-repellant pesticide to form a foamable liquid pesticide formulation should also be non-repellant. Otherwise, if the adjuvant added to the non-repellant pesticide is to a greater or lesser extent repellant, a pesticide that in of itself is non-repellant, applied as a foam becomes repellant to the degree that the adjuvant is repellant thereby making the pesticide less effective or possibly ineffective.
In addition, the adjuvant added to a non-repellant pesticide to form a foamable liquid pesticide formulation should be nonionic so that the pesticide molecules in the coating, film or layer left after the foam breaks down are not held by the adjuvant in the coating, film or layer, but are easily released upon contact to contaminate the pests being controlled. Accordingly, for non-repellant pesticides applied as foams to be most effective, the adjuvant of the foamable liquid pesticide formulations used to form the pesticide foams must be both non-repellant and nonionic. To applicant""s knowledge, the adjuvants added to these non-repellant pesticides to form foamable liquid pesticide formulations have not contained adjuvants that are non-repellant and/or nonionic. Accordingly, there has been a need to provide a more effective method of pest control through the use of non-repellant pesticides in foamable formulations that do not include other ingredients that will repel the pests or retain the pesticide molecules in the formulation.
The small lightweight portable hand held foam generation equipment, the foamable liquid pesticide formulation with its non-repellant and nonionic adjuvant, and the method of controlling pests with the foamable liquid pesticide formulation of the present invention provide a solution to the above discussed problems of the prior art. As used herein the term xe2x80x9cpesticidexe2x80x9d includes but is not limited to termiticides, fungicides, herbicides, growth regulators, particles of bait treated or impregnated with agents that destroy pests, and other agents used to destroy pests.
The small lightweight portable hand held foam generation equipment of the present invention may be easily and readily used by both home handymen/women (do-it-your-selfers) and commercial contractors to foam various foamable liquids at different volumetric expansion ratios between 2 to 1 and 25 to 1 with volumetric expansion ratios between 6 to 1 and 20 to 1 or between 15 to 1 and 20 to 1 being typical of the volumetric increases selected for most applications. In addition to being inexpensive, readily portable, easy to use, and having a high foam discharge rate, with its uniquely simplified construction, the foam generation equipment of the present invention is easy and inexpensive to maintain.
The hand held foam generator of the present invention includes an airtight reservoir for containing a foamable liquid and is pressurized with air through an air pump that is integral with the hand held foam generator or a source of pressurized air connected by air supply lines to the reservoir of the hand held foam generator. In one preferred embodiment, the foam generator includes a foam dispensing assembly, e.g. a conventional foam application gun, mounted directly on the reservoir and a unique discharge tube that extends from the foam dispensing assembly down into the reservoir for discharging the foamable liquid from the reservoir as a fluid foam through the foam dispensing assembly. Preferably, the discharge tube is both flexible and weighted, at or adjacent the bottom of the tube, to cause the discharge tube to move in any direction that the foamable liquid moves when the foam generation equipment is tilted. Thus, when the hand held foam generation equipment of the present invention is moved, turned or tilted in any of numerous directions while in use, the lower end of discharge tube will continue to be immersed in the foamable liquid in the reservoir and continue to withdraw the foamable liquid from the reservoir.
The discharge tube has one or more venturi openings, above a maximum foamable liquid fill line of the reservoir, for introducing pressurized air within the reservoir into the discharge tube. Although it is preferred for ease of use to have a maximum foamable liquid fill line marking on the reservoir to aid the user in filling the reservoir to its maximum selected capacity, as used herein, the term xe2x80x9cmaximum foamable liquid fill line of the reservoirxe2x80x9d does not have to be an actual marking on the reservoir, but is a level at or below which a foamable liquid should be maintained in the reservoir to assure that the foamable liquid does not cover a venturi opening in the discharge tube. The pressurized air introduced into the discharge tube through the one or more venturi openings mixes with the foamable liquid as the foamable liquid is discharged from the reservoir by the pressurized air through the discharge tube to form a fluid foam. The fluid foam is dispensed by the foam dispensing assembly and is spread by a process called xe2x80x9cstackingxe2x80x9d or otherwise flows over and into the space or spaces being treated to fully wet, impregnate and/or coat all of the surfaces within the space or spaces including porous surfaces, cracks in the surfaces, joints, and passageways and the entrances of passageways leading into or out of the space or spaces.
For certain applications where the foam generation equipment is set up to produce a foam from a particular foamable liquid formulation at a particular volumetric expansion ratio and increased volumetric expansion ratios are desired to form a dryer foam for a portion of the application or for a different application, a foam expansion chamber may be added to the foam dispensing assembly to further mix the air with the foam coming from the reservoir to obtain the desired increase in the volumetric expansion of the foam. The particular foam expansion chamber added to the foam dispensing assembly is selected to provide the additional volumetric expansion desired. While conventional foam expansion chambers utilizing stainless steel wool or a form 3M Scotch brand brite pad may be attached to the foam dispensing assembly, preferably, the foam expansion chamber includes an inlet tube with one or more venturi openings therein to create a vortex action within the foam as the foam passes through the chamber. In addition, a foam expansion chamber may be utilized to maintain the same volumetric expansion ratio at lower than normal operating pressures, e.g. operating pressures below 15 pounds per square inch gauge.
The foamable liquid non-repellant pesticide formulation of the present invention includes a pesticide that is non-repellant to a selected type of pest and a foaming agent or surfactant adjuvant, blended or mixed with the non-repellant pesticide, that is non-repellant to the particular pest being treated and, preferably, also nonionic to facilitate the contamination of the pests with molecules of the pesticide.
With respect to pest control, the hand held foam generation equipment of the present invention enables new procedures to be utilized in the treatment of various pests with foam pesticides. In addition to termites, pests, such as but not limited to carpenter ants, cockroaches, bees, wasps, hornets, fire ants and drain flies, have traditionally been controlled through the injection of liquid pesticides into soil, liquid pesticides sprayed onto or into pest habitats, the fumigation of spaces with gas or dust pesticides, or the inclusion of pesticides in baits. With the small, lightweight, portable, high foam output foam generation equipment of the present invention, these and other pests can also be controlled through the use of foam pesticides and especially through the use of foam pesticides formed from the foamable non-repellant liquid pesticide formulation of the present invention.
For example, the small, lightweight, portable, high foam output foam generation equipment of the present invention enables pest control workers, unencumbered by heavy and awkward to use equipment, to easily and quickly apply fluid foam pesticides, preferably formed from the foamable non-repellant liquid pesticide formulation of the present invention, to numerous fire ant colonies spread out over a large area. In addition, by applying the fluid foam pesticide to the ground in an area surrounding the main entrance(s) to the colony before applying the foam pesticide to the main entrances, ants will not be able to move across the ground to attack the pest control worker and auxiliary entrances used by the colony to attack an intruder such as the pest control worker can be temporarily sealed by the foam to prevent the ants from attacking the pest control worker. After the foam breaks down, a coating, film or layer of pesticide covers the entrances to and at least upper portions of passageways down into the colony nest and the ground surrounding the nest. When the foamable non-repellant liquid pesticide formulation of the present invention is used to form the foam pesticide, ants continue to move through the passageways and over the ground treated with the pesticide and make contact with the pesticide that is transferred by such contact to their bodies. The pesticide is then spread throughout the colony in a manner similar to that discussed above in connection with termites.
In another example of the versatility of the small, lightweight, portable, high foam output foam generation equipment of the present invention, the foam generation equipment of the present invention enables pest control workers, unencumbered by heavy and awkward to use equipment, to easily and quickly apply foam pesticides to bee hives, wasp nests, hornet nests, etc., even when these hives or nests are located in relatively inaccessible locations. As an aid, one or more lightweight, rigid or semi-rigid dispensing tubes, each from one to two meters long, or a telescoping dispensing tube of two or more sections, each from one to two meters long, can be attached to the foam dispensing assembly to deliver the fluid foam pesticide to hives or nests high above the ground or otherwise not readily accessible. The application of the fluid foam pesticide to the hive or nest during treatment temporarily seals the entrances to the hive or nest thereby protecting the pest control worker during the application of the pesticide. After the foam breaks down, a coating, film or layer of pesticide covers not only the entrances to and at least outer portions of passageways leading into the hive or nest but also the outer surfaces of the hive or nest. When the non-repellant foam pesticide of the present invention is used, bees, wasps, hornets or other pests continue to move through the passageways and over the hive or nest and contact the pesticide that is transferred by such contact to their bodies. The pesticide is then spread throughout the colony in a manner similar to that discussed above in connection with termites.
While the portable hand held foam generation equipment of the present invention is especially well suited for use in pest control applications, it should be noted that the portable hand held foam generation equipment of the present invention is also very well suited for many other applications where light weight, portable, easy to use and manipulate, hand held foam generators would be required or desired. For example, the foam generation equipment of the present invention may be used by a home handyman/woman or a commercial contractor or business: to apply a foam cleaner to the tires or the engine of a vehicle or aircraft, to a apply an anti-bacterial foam to the walls of a meat packing room, and to apply foams in many other applications where the application of a material to a surface, exposed or relatively inaccessible, is desired to coat, impregnate or otherwise treat the surface.